Phonon‐assisted energy transfer in Er‐exchanged LiNbO ₃

Abstract

Raman microprobe spectroscopy measurements show, that in contrast to Er-idiffusion, Er-exchange proc- ess leads to significant change of the lattice vibration spectrum of LiNbO3. Therefore, our data allow to assume that the drastic suppression of parasitic upconversion in the Er-exchanged LiNbO3 are caused by multiphonon nonradiative decay of the 2(4F9/2) state, providing fast nonradiative energy transfer to the 4G11/2 and (4F7/2+4I13/2) states